![]() When the constructor of the derived class invokes a constructor of the parent class, either explicitly or implicitly, a whole chain of constructors is called all the way back to the constructor of object.If the super class does not have a default constructor a compile time error will be displayed on the screen. It will automatically insert a call to the no-argument or the default constructor of the super class. If the constructor of the derived class does not explicitly call or invoke the base class constructor then the Java compiler will take over.Else a compile time error message will be displayed on the screen. Call to super() MUST be the first statement in the derived / child class constructor.In the above example, we have called the super / parent class constructor using the super() keyword via the sub / child class. ![]() As constructors are both parameterised and non-parameterised, we can make use of the super keyword to call either of these constructors depending on the situation. Super keyword is also used to access the constructors of the parent class. In the above example we can clearly see that when we call the method by its name only then the method of the child class is invoked and when we make use of the super keyword, then the method of the super class is invoked. Super.msg() // invokes parent class method So when the parent and the child class have the same name for a method, so to resolve the ambiguity we make use of the super keyword to access the parent class method in the base class. This is used when we want to make a call to the parent class method. If the immediate superclass does not have the default constructor (it defines some constructors but does not define a no-arg constructor), you will get a. Here, we are accessing the speed variable of the parent class in the sub class with the help of the super keyword. This is done using the super () keyword, which calls the constructor of the parent class. Here are some of its characteristics: super is used to call a superclass constructor: When a subclass is created, its constructor must call the constructor of its parent class. ![]() Therefore, java does not allow final keyword before a constructor. In Java, the super keyword is used to refer to the parent class of a subclass. In this example, both the classes have the same variable speed. In other words, constructors cannot be inherited in Java, hence, we cannot override them. The constructor is called when an object of a class is created.
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